Season 03- The Tamers
Takato receiving his   D-Power. (Sorry about the size, that's as big as I could get the pictures)
Henry's card reader becomes a D-Power as well.
Rika gets hers after winning a card championship.
Takato
Takato is a rookie trainer. He gets his D-Power after swiping a blue card on his card reader. After being punished by his teacher, he draws a digimon called Guilmon. That night, the picture gets swiped through his D-Power and an egg appears. The egg hatches and Guilmon bio-emerges.

At first, Takato has trouble fighting digimon with Guilmon but its not because he can't control Guilmon, it's  because he is a crummy Tamer. He learns, however, and gets quite good.
Henry
Henry was already a tamer when Takato created Guilmon, so we don't learn much about him until later.
He gets his D-Power after playing a digimon game on his computer. Terriermon (on the game) had just beaten Gorillamon. Henry then found a blue card (at least I think he did, I'll have to rewatch the episode) and swiped it. His card reader turned into a D-Power as well.

Henry treats digimon as equals. He believes they aren't just partners, but friends. Although Terriermon always seems to find trouble, Henry never gets mad; he just scolds Terriermon.
Rika
We first see Rika in episode 1, we just don't realize it 'till later. She is seen in a dream of Takato's, taming Renamon as she fights Lynxmon.
When we actually meet her, she turns out to be a tough girl who likes to fight and believes digimon are just bits of data and doesn't treat Renamon as nicely as Takato and Henry treat their digimon. Later, after Renamon is almost destroyed (more than once), she finally realizes that Renamon is a living creature, her partner, and her friend. She then joins Takato and Henry willingly. A lot of her attitude seems to come from her mother, who is a fashion model and doesn't seem to pay much attention to Rika.
Terriermon
Guilmon
Renamon
Guilmon is a powerful and (according to my sister and Jeri) cute digimon. Takato created him to be a powerful fighter and when he first met Guilmon, he was scared of him. He soon came to realize that Guilmon is a friendly, bread-loving goof (Takato's own words). His attack is Pyro-sphere and he digivolves into Growlmon and then into WarGrowlmon. His mega level is Gallantmon but he hasn't reached it yet.
Guilmon's Digivolutions
Terriermon's Digivolutions
Renamon's Digivolutions
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